Imported Upstream version 5.18.0.207

Former-commit-id: 3b152f462918d427ce18620a2cbe4f8b79650449

external/llvm/lib/Transforms/ObjCARC/ObjCARCExpand.cpp

@@ -1,127 +0,0 @@
-//===- ObjCARCExpand.cpp - ObjC ARC Optimization --------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-/// \file
-/// This file defines ObjC ARC optimizations. ARC stands for Automatic
-/// Reference Counting and is a system for managing reference counts for objects
-/// in Objective C.
-///
-/// This specific file deals with early optimizations which perform certain
-/// cleanup operations.
-///
-/// WARNING: This file knows about certain library functions. It recognizes them
-/// by name, and hardwires knowledge of their semantics.
-///
-/// WARNING: This file knows about how certain Objective-C library functions are
-/// used. Naive LLVM IR transformations which would otherwise be
-/// behavior-preserving may break these assumptions.
-///
-//===----------------------------------------------------------------------===//
-
-#include "ObjCARC.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/InstIterator.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/Value.h"
-#include "llvm/Pass.h"
-#include "llvm/PassAnalysisSupport.h"
-#include "llvm/PassRegistry.h"
-#include "llvm/PassSupport.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-
-#define DEBUG_TYPE "objc-arc-expand"
-
-namespace llvm {
-  class Module;
-}
-
-using namespace llvm;
-using namespace llvm::objcarc;
-
-namespace {
-  /// \brief Early ARC transformations.
-  class ObjCARCExpand : public FunctionPass {
-    void getAnalysisUsage(AnalysisUsage &AU) const override;
-    bool doInitialization(Module &M) override;
-    bool runOnFunction(Function &F) override;
-
-    /// A flag indicating whether this optimization pass should run.
-    bool Run;
-
-  public:
-    static char ID;
-    ObjCARCExpand() : FunctionPass(ID) {
-      initializeObjCARCExpandPass(*PassRegistry::getPassRegistry());
-    }
-  };
-}
-
-char ObjCARCExpand::ID = 0;
-INITIALIZE_PASS(ObjCARCExpand,
-                "objc-arc-expand", "ObjC ARC expansion", false, false)
-
-Pass *llvm::createObjCARCExpandPass() {
-  return new ObjCARCExpand();
-}
-
-void ObjCARCExpand::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.setPreservesCFG();
-}
-
-bool ObjCARCExpand::doInitialization(Module &M) {
-  Run = ModuleHasARC(M);
-  return false;
-}
-
-bool ObjCARCExpand::runOnFunction(Function &F) {
-  if (!EnableARCOpts)
-    return false;
-
-  // If nothing in the Module uses ARC, don't do anything.
-  if (!Run)
-    return false;
-
-  bool Changed = false;
-
-  DEBUG(dbgs() << "ObjCARCExpand: Visiting Function: " << F.getName() << "\n");
-
-  for (inst_iterator I = inst_begin(&F), E = inst_end(&F); I != E; ++I) {
-    Instruction *Inst = &*I;
-
-    DEBUG(dbgs() << "ObjCARCExpand: Visiting: " << *Inst << "\n");
-
-    switch (GetBasicARCInstKind(Inst)) {
-    case ARCInstKind::Retain:
-    case ARCInstKind::RetainRV:
-    case ARCInstKind::Autorelease:
-    case ARCInstKind::AutoreleaseRV:
-    case ARCInstKind::FusedRetainAutorelease:
-    case ARCInstKind::FusedRetainAutoreleaseRV: {
-      // These calls return their argument verbatim, as a low-level
-      // optimization. However, this makes high-level optimizations
-      // harder. Undo any uses of this optimization that the front-end
-      // emitted here. We'll redo them in the contract pass.
-      Changed = true;
-      Value *Value = cast<CallInst>(Inst)->getArgOperand(0);
-      DEBUG(dbgs() << "ObjCARCExpand: Old = " << *Inst << "\n"
-                      "               New = " << *Value << "\n");
-      Inst->replaceAllUsesWith(Value);
-      break;
-    }
-    default:
-      break;
-    }
-  }
-
-  DEBUG(dbgs() << "ObjCARCExpand: Finished List.\n\n");
-
-  return Changed;
-}